U.S. presidents and some activist groups have called the bloody campaign by the Sudanese Arab-led government and allied militias 'genocide.' But others doubt the violence fits the legal definition.

EL FASHER, SUDAN — What if the conflict many call the "first genocide of the 21st century" weren't one at all?

In the United States, many see the six-year war in Darfur as a bloody campaign by a Sudanese Arab-dominated government against rebellious "African" tribes in western Sudan. Two consecutive American presidents and several activist groups have defined it as genocide.

But others, while acknowledging the severity of the violence, question whether it meets the legal definition of genocide. The United Nations determined in 2005 that the Sudanese government wasn't committing genocide in Darfur. Human Rights Watch and Doctors Without Borders avoid the G-word too.

The International Criminal Court renewed the debate in March when it issued an arrest warrant for Sudanese President Omar Hassan Ahmed Bashir. Judges said his counterinsurgency tactics in Darfur may amount to war crimes and crimes against humanity, but that there was no evidence of genocide.

The debate raises touchy and politically explosive questions: What constitutes genocide? Why does -- or doesn't -- Darfur fit the mold? Has the label helped, or hurt, the people of Darfur? And what does it matter anyway if what has occurred in Darfur is viewed as genocide rather than, say, war crimes or "ethnic cleansing"?

Most agree that it has mattered a lot.

When former U.S. Secretary of State Colin L. Powell first described Darfur as a case of genocide in 2004, a $1-billion-a-year international aid effort quickly followed, elevating the crisis above other African conflicts, including those in Somalia and Congo, where the mortality rates in recent years have been higher and the displacement greater.

"The word 'genocide' has so much power," said Neha Erasmus, program coordinator for Justice Africa in London. "Darfur really took hold of the American psyche after it was called genocide."

But the global attention also brought heightened politics and at times led to resources being misdirected, aid workers say.

A misconception that hundreds of people are dying each day in Darfur has led many in the West to push for emergency security measures such as military intervention, U.N. peacekeepers and no-fly zones, and to overlook larger issues such as stalled peace talks and millions of people dependent on foreign aid, said Thierry Durand, director of operations for Doctors Without Borders.

"The magnitude of violence in Darfur has been huge, but it's not genocide," Durand said. "The situation on the ground has not been an emergency since 2004. The real problem is the dependency in the camps. But the whole thing has become over-politicized."

The genocide label also may have prolonged the conflict by raising the stakes and complicating peace talks, experts and diplomats say.

"Genocide puts a moral price on this that limits the room to maneuver," said one Western diplomat in Khartoum, the Sudanese capital, who did not want to be identified because of the sensitivity of the topic. "How can you deal with a genocidal government? Can you compromise with evil?"

John Prendergast, a former Clinton administration advisor and founder of one of the advocacy groups that have lobbied the United States to declare the Darfur violence a genocide, said the "invocation of that word saved hundreds of thousands of lives. Absent that, it would have been harder to get this on the radar screen."

But he dismissed the is-it-or-isn't-it controversy as legal semantics. "Well-meaning scholars can disagree, but the debate is a crushing diversion from what we need to do to find a solution," he said.

It's a question now facing President Obama. As a candidate, Obama opposed attempts to normalize Sudanese relations, accusing the Bush administration of trying to reward a brutal regime.

As president, Obama is navigating that rhetoric as he searches for an end to the crisis. His ambassador to the U.N., Susan Rice, describes the situation in Darfur as an "ongoing genocide," but his new envoy to Sudan, J. Scott Gration, called the nation a "friend" and reopened the door to improved ties during a recent visit to Khartoum.

To many, such a policy sets a dangerous precedent. A determination of genocide should trigger immediate action to end the killing, including military intervention if necessary, legal experts say.

But after the U.S. described the Darfur bloodshed as genocide, its policy consisted of economic sanctions and diplomatic pressure.

"If this is the first genocide of the 21st century, why the heck are we talking about travel bans and asset freezes?" asked Alex De Waal, a noted Sudan expert and program director with the nonprofit Social Science Research Council. "Would you do that with Hitler?"

De Waal, who does not consider the campaign in Darfur genocide, said the U.S. stance has "diluted" the sense of international urgency that should accompany a finding of genocide.